Some people like the Vanco pieces and say they never have problems with them. Some people like the smell of their own poo, who am I to argue with what they like.

The point is: HDMI is finicky enough; why are you adding a piece of equipment in-line with the HDMI signal, that does NOT need to be there? There is a dedicated audio output on the Roku4, in the form of a Toslink connector.
If you need analog audio, then put a converter on that. Problem solved (at least this 1 problem, for right now).
Is there a location issue, why you have to get the audio from the HDMI for some reason?